1.Evaluation of the Promoter Activity of the CHO Cell Expression System Based on Site-specific Integration
Chen LU ; Zi-Yu WANG ; Yan-Fei CAI ; Yong-Qiang DENG ; Jian JIN ; Xue-Feng DING ; Yun CHEN
Chinese Journal of Biochemistry and Molecular Biology 2024;40(10):1400-1408
In industrial production,the expression level of drug proteins in Chinese hamster ovary cells(CHO)is influenced by many factors:the regulatory elements on transcription and translation,the ge-nomic integration sites,and the expression system.Transcription,as the first step of gene expression,largely affects protein expression,and the promoter plays a crucial role in the initiation of transcription.Most of the promoters were screened through transient transfection or random integration,but the presence of unclear copy number or random integration sites makes it difficult to accurately evaluate the promoter activity.To some extent,site-specific integration can reduce the impact of positional effects on exogenous genes and may potentially increase the expression level of exogenous genes.In the early stage of our re-search,multiple sites that can stably express exogenous proteins were identified and verified in the CHO cell genome.In this study,one of these sites(2c6)was selected for the evaluation of promoter activity.The CRISPR/Cas9 gene editing technique was used to site-specifically integrate the reporter gene(EG-FP)regulated by the simian virus early promoter(SV40),mouse elongation factor-1α(mEF-1α),chicken β-actin(cACTB)promoter,and human phosphoglycerate kinase promoter(hPGK)into the 2c6 site,respectively.The mean fluorescence intensity of the cells was analyzed by flow cytometry,and the mRNA level of EGFP was detected by qPCR to comprehensively evaluate the activity of the promoter.The results showed that the activities of the mEF-1α and mACTB promoters were better than those of SV40 and hPGK.The results of the secondary flow cytometry sorting showed that site-specific integration can more accurately evaluate the activity of the promoter in the CHO cell expression system.
2.Establishment of a Multiplex Detection Method for Common Bacteria in Blood Based on Human Mannan-Binding Lectin Protein-Conjugated Magnetic Bead Enrichment Combined with Recombinase-Aided PCR Technology
Jin Zi ZHAO ; Ping Xiao CHEN ; Wei Shao HUA ; Yu Feng LI ; Meng ZHAO ; Hao Chen XING ; Jie WANG ; Yu Feng TIAN ; Qing Rui ZHANG ; Na Xiao LYU ; Qiang Zhi HAN ; Xin Yu WANG ; Yi Hong LI ; Xin Xin SHEN ; Jun Xue MA ; Qing Yan TIE
Biomedical and Environmental Sciences 2024;37(4):387-398
Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannan-binding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP. Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays. Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05). Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.
3.CCTA based clinical value analysis of ΔCT-FFR in evaluating coronary artery function in patients with severe calcification
Kai WEI ; Xi WANG ; Bai HE ; Zi-Qiang ZHAO ; Wei ZHANG ; Jing JING ; Dong-Kai SHAN
Medical Journal of Chinese People's Liberation Army 2024;49(2):144-151
Objective To investigate the clinical value of coronary computed tomography angiography(CCTA)based CT derived fractional flow reserve(CT-FFR)and ΔCT-FFR in improving the diagnostic efficiency for coronary abnormal hemodynamics in patients with severe calcification.Methods We retrospectively analyzed the clinical data of coronary artery disease(CAD)patients who underwent CCTA,CT-FFR,invasive coronary angiography(ICA)and FFR during hospitalization from January 2018 to June 2019 in Chinese PLA General Hospital.Severe calcification was defined as coronary artery calcium score(CACS)≥100 on single vessel level.A total of 107 CAD patients with 149 coronary arteries were included in the present study.The enrolled coronary arteries were assigned to CACS≥100 group(n=56)and CACS<100 group(n=93).CT-FFR was performed on the deep FFR platform based on machine learning(ML)algorithms and ΔCT-FFR was defined as CT-FFR difference between proximal and distal to the coronary lesion.The correlation and consistency between CT-FFR and FFR values were analyzed by Pearson and Bland-Altman methods.We attempted to analyze the incremental value of ΔCT-FFR for coronary functional evaluation,especial for coronary arteries with severe calcification,regarding FFR≤0.8 as the diagnostic gold standard.Comparison of receiver operating characteristic curves(ROC)between different diagnostic methods was presented by Delong test.Results Pearson and Bland-Altman analyses showed appreciable correlation(CACS≥100 group,r=0.71,P<0.01;CACS<100 group,r=0.73,P<0.01)and consistency(CACS≥100 group,Mean=-0.01,P=0.25;CACS<100 group,Mean=0,P=0.96)between CT-FFR and FFR values in both groups.FFR(0.80±0.08 vs.0.84±0.09,P=0.004)and CT-FFR(0.81±0.06 vs.0.85±0.06,P<0.001)levels were significant lower in CACS≥100 group than those in CACS<100 group,while ΔCT-FFR(0.14±0.06 vs.0.09±0.06,P<0.001)levels were significant higher in CACS≥100 group.Moreover,the diagnostic efficiency of CT-FFR in CACS≥100 group was inferior to that in CACS<100 group[AUC=0.792(95%CI 0.663-0.889)vs.AUC=0.929(95%CI 0.856-0.972),P=0.04],while it achieved significant improvement after ΔCT-FFR adjustment[AUC=0.876(95%CI 0.760-0.949)vs.AUC=0.792(95%CI 0.663-0.889),P=0.02]and was similar to that in CACS<100 group(P=0.37).Conclusion For coronary arteries with severe calcification,CT-FFR demonstrated significant incremental value in improving the diagnostic efficiency of coronary abnormal hemodynamics after ΔCT-FFR adjustment.
4.The impact of short-course total neoadjuvant therapy, long-course chemoradiotherapy, and upfront surgery on the technical difficulty of total mesorectal excision: an observational study with an intraoperative perspective
Cheryl Xi-Zi CHONG ; Frederick H. KOH ; Hui-Lin TAN ; Sharmini Su SIVARAJAH ; Jia-Lin NG ; Leonard Ming-Li HO ; Darius Kang-Lie AW ; Wen-Hsin KOO ; Shuting HAN ; Si-Lin KOO ; Connie Siew-Poh YIP ; Fu-Qiang WANG ; Fung-Joon FOO ; Winson Jianhong TAN
Annals of Coloproctology 2024;40(5):451-458
Purpose:
Total neoadjuvant therapy (TNT) is becoming the standard of care for locally advanced rectal cancer. However, surgery is deferred for months after completion, which may lead to fibrosis and increased surgical difficulty. The aim of this study was to assess whether TNT (TNT-RAPIDO) is associated with increased difficulty of total mesorectal excision (TME) compared with long-course chemoradiotherapy (LCRT) and upfront surgery.
Methods:
Twelve laparoscopic videos of low anterior resection with TME for rectal cancer were prospectively collected from January 2020 to October 2021, with 4 videos in each arm. Seven colorectal surgeons assessed the videos independently, graded the difficulty of TME using a visual analog scale and attempted to identify which category the videos belonged to.
Results:
The median age was 67 years, and 10 patients were male. The median interval to surgery from radiotherapy was 13 weeks in the LCRT group and 24 weeks in the TNT-RAPIDO group. There was no significant difference in the visual analog scale for difficulty in TME between the 3 groups (LCRT, 3.2; TNT-RAPIDO, 4.6; upfront, 4.1; P=0.12). A subgroup analysis showed similar difficulty between groups (LCRT 3.2 vs. TNT-RAPIDO 4.6, P=0.05; TNT-RAPIDO 4.6 vs. upfront 4.1, P=0.54). During video assessments, surgeons correctly identified the prior treatment modality in 42% of the cases. TNT-RAPIDO videos had the highest recognition rate (71%), significantly outperforming both LCRT (29%) and upfront surgery (25%, P=0.01).
Conclusion
TNT does not appear to increase the surgical difficulty of TME.
5.Clinical diagnosis and treatment of hereditary thrombocytopenia and purpura: a report of five cases and literature review.
Xin Bo LYU ; Jie YIN ; Dan Qing KONG ; Hong TIAN ; Yun LI ; Q QYU ; Jian SU ; Li Juan CAO ; Xia BAI ; Zi Qiang YU ; Zhao Yue WANG ; De Pei WU ; Chang Geng RUAN
Chinese Journal of Hematology 2023;44(1):43-47
Objective: To report the clinical manifestations and laboratory features of five patients with congenital thrombotic thrombocytopenic purpura (cTTP) and explore its standardized clinical diagnosis and treatment along with a review of literature. Methods: Clinical data of patients, such as age of onset, disease manifestation, personal history, family history, and misdiagnosed disease, were collected. Treatment outcomes, therapeutic effects of plasma infusion, and organ function evaluation were observed. The relationship among the clinical manifestations, treatment outcomes, and ADAMTS13 gene mutation of patients with cTTP was analyzed. Additionally, detection of ADAMTS13 activity and analysis of ADAMTS13 gene mutation were explored. Results: The age of onset of cTTP was either in childhood or adulthood except in one case, which was at the age of 1. The primary manifestations were obvious thrombocytopenia, anemia, and different degrees of nervous system involvement. Most of the patients were initially suspected of having immune thrombocytopenia. Acute cTTP was induced by pregnancy and infection in two and one case, respectively. ADAMTS13 gene mutation was detected in all cases, and there was an inherent relationship between the mutation site, clinical manifestations, and degree of organ injury. Therapeutic or prophylactic plasma transfusion was effective for treating cTTP. Conclusions: The clinical manifestations of cTTP vary among individuals, resulting in frequent misdiagnosis that delays treatment. ADAMTS13 activity detection in plasma and ADAMTS13 gene mutation analysis are important bases to diagnose cTTP. Prophylactic plasma transfusion is vital to prevent the onset of the disease.
Female
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Pregnancy
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Humans
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Adult
;
Blood Component Transfusion
;
Plasma
;
Purpura, Thrombotic Thrombocytopenic/therapy*
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Mutation
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Purpura, Thrombocytopenic, Idiopathic
;
ADAMTS13 Protein/therapeutic use*
7.A real-world study of the effects of endocrine therapy on liver function in breast cancer.
Yue Chong LI ; Zi Xin DENG ; Ying Jiao WANG ; Tao XU ; Qiang SUN ; S J SHEN
Chinese Journal of Surgery 2023;61(2):107-113
Objective: To compare the effect of different endocrine therapy drugs on liver function in patients with early breast cancer. Methods: A retrospective cohort study was conducted to include 4 318 patients with early breast cancer who received adjuvant endocrine therapy in Department of Breast Surgery, Peking Union Medical College Hospital from January 1, 2013 to December 31, 2021. All the patients were female, aged (51.2±11.3) years (range: 20 to 87 years), including 1 182 patients in the anastrozole group, 592 patients in the letrozole group, 332 patients in the exemestane group, and 2 212 patients in the toremifene group. The mixed effect model was used to analyze and compare the liver function levels of patients at baseline, 6, 12, 18, 24, 36, 48, 60 months of medication, and 1 year after drug withdrawal among the three aromatase inhibitors (anastrozole, letrozole, exemestane) and toremifene. Results: ALT and AST of the 4 groups were significantly higher than the baseline level at 6 months (all P<0.01), and there were no significant differences in total bilirubin, direct bilirubin and AST levels among all groups one year after drug withdrawal (P: 0.538, 0.718, 0.061, respectively). There was no significant difference in the effect of all groups on AST levels (F=2.474, P=0.061), and in the effect of three aromatase inhibitors (anastrozole, letrozole, and exemestane) on ALT levels (anastrozole vs. letrozole, P=0.182; anastrozole vs. exemestane, P=0.535; letrozole vs. exemestane, P=0.862). Anastrozole and letrozole had significantly higher effects on ALT levels than toremifene (P<0.01, P=0.009). The proportion of abnormal liver function in each group increased significantly at 6 months compared with baseline, and then the proportion showed a decreasing trend over time. Conclusions: Three aromatase inhibitors (anastrozole, letrozole, and exemestane) and toremifene can significantly increase the level of ALT and AST in patients with breast cancer, and the levels can gradually recover to the baseline after 1 year of drug withdrawal. The effect of non-steroidal aromatase inhibitors (anastrozole, letrozole) on ALT levels is greater than toremifene.
Female
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Humans
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Anastrozole
;
Aromatase Inhibitors/therapeutic use*
;
Bilirubin
;
Breast Neoplasms/drug therapy*
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Letrozole
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Liver
;
Retrospective Studies
;
Toremifene
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Young Adult
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Adult
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Middle Aged
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Aged
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Aged, 80 and over
8.Clinical features and antimicrobial resistance of invasive non-typhoid Salmonella infection in children at Xiamen.
Cai Hong WANG ; Mei Lian HUANG ; Zhi Qiang ZHUO ; Zi Xuan WANG ; Lei CHEN ; Yi Qing SONG ; Hui YU
Chinese Journal of Pediatrics 2023;61(8):685-689
Objective: To investigate the clinical characteristics, serogroups and antimicrobial resistance of invasive non-typhoid Salmonella infection in children at Xiamen. Methods: Retrospective cohort study. The clinical manifestations, treatment, prognosis, serogroups and antimicrobial resistance of 29 hospitalized children with invasive non-typhoid Salmonella infection confirmed by blood, cerebrospinal fluid, bone marrow and other sterile body fluids or deep pus culture at the Department of Infectious Diseases, the Department of Orthopedics and the Department of General Surgery in Xiamen Children's Hospital from January 2016 to December 2021 were analyzed. According to the clinical diagnosis criteria, the patients were divided into sepsis group and non-sepsis group (bacteremia and local suppurative infection). The inflammatory markers, serogroups distribution and drug resistance were compared between the two groups. Comparison between groups using Mann-Whitney U test and χ2 test. Results: Among the 29 cases, there were 17 males and 12 females, with an onset age of 14 (9, 25) months, and 10 cases (34%) of patients were younger than 1 year old, 15 cases (52%) under 1 to 3 years old, and 4 cases (14%) greater than or equal 3 years old. The onset time of 25 cases (86%) was from April to September. The diseases included 19 cases (66%) septicemia (2 of which were combined with suppurative meningitis), 10 cases (34%) non-sepsis group, including 7 cases bacteremia and 3 cases local suppurative infection (2 cases of osteomyelitis, 1 case of appendicitis with peritonitis). The clinical manifestations were fever in 29 cases (100%), diarrhea and abdominal pain in 18 cases (62%), cough and runny nose in 10 cases (34%). Eighteen cases (62%) were cured and 11 cases (38%) were improved by effective antibiotics treatment. C-reactive protein in sepsis group was significantly higher than that in non-sepsis group (25.2 (16.1, 56.4) vs. 3.4 (0.5, 7.5) mg/L, Z=-3.81, P<0.001).The serogroups of C, B and E were the most prevalent among non-typhoid Salmonella isolates, accounting for 10 cases (34%), 9 cases (31%) and 7 cases (24%) respectively. Antibacterial drug sensitivity test showed that the sensitivity rates of imipenem, ertapenem and piperaciratazobactam were all 100% (31/31), those of ceftazidime, ceftriaxone, and cefepime were 94% (29/31), 94% (29/31) and 97% (30/31) respectively. The drug resistance rates of ampicillin, ampicillin-sulbactam and trimethoprim-sulfamethoxazole were 51% (16/31), 48% (15/31) and 48% (15/31) respectively, those of cefazolin, cefotetan, tobramycin, gentamicin and amikacinwere all 100% (31/31). There were no significant differences in the drug resistance rates of ceftazidime, ceftriaxone, aztreonam, ampicillin-sulbactam, ampicillin, trimethoprim-sulfamethoxazole and ciprofloxacin between the sepsis group and the non-sepsis group (χ2=0.31,0.31,0.00,0.02,0.02,0.02,0.26, all P>0.05). Conclusions: Invasive non-typhoid Salmonella infection in children at Xiamen mainly occurred in infants younger than 3 years old.The main clinical manifestations are fever, abdominal pain and diarrhea. C-reactive protein can be served as the laboratory indicators for indicating sepsis. The third generation of cephalosporins is recommended as the first choice for treatment.
Infant
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Male
;
Female
;
Child
;
Humans
;
Child, Preschool
;
Anti-Bacterial Agents/therapeutic use*
;
Ceftriaxone/therapeutic use*
;
Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use*
;
Ceftazidime/therapeutic use*
;
Retrospective Studies
;
C-Reactive Protein
;
Drug Resistance, Bacterial
;
Salmonella Infections/microbiology*
;
Ampicillin/therapeutic use*
;
Salmonella
;
Diarrhea/drug therapy*
;
Bacteremia
;
Abdominal Pain
;
Microbial Sensitivity Tests
9. A cell model for high-throughput screening GLP-1 receptor agonists
Rui WANG ; Zi-Xin YANG ; Zhi-Qiang KE ; Zheng-Ding SU ; Zhi-Qiang KE ; Xi-Yao CHENG
Chinese Pharmacological Bulletin 2023;39(9):1793-1798
Aim To establish a high-throughput screening cell model for GLP-1 receptor agonists. Methods A pEGFP-GLP-1R-3 C recombinant plasmid was constructed and transfected into HEK293T cells. The cells were screened with G418 and flow cytometry. The established stable cell line was named HEK293TGLP-lR-3C-eGFP cell line. The expression level of GLP-1 R-3C-eGFP protein was confirmed by Western blotting and laser confocal microscopy. Then cyclic adenosine monophosphate (cAMP) response element reporter gene was transfected into the HEK293T-GLP-lR-3C-eGFP cells. The luminescence values were detected by One-Step Luciferase Reporter Gene Assay Kit after stimulation with different concentrations of GLP-1 peptide. The luminescence values reflected the cellular cAMP level, which was verified using the cAMP kit (E L I S A). Results HEK293T-GLP-lR-3C-eGFP cell line was successfully constructed. The relative light unit change trend after stimulation with different concentrations of GLP-1 was similar to that of the cellular cAMP level change trend. The value of Z' in this experiment was 0.52. Conclusions A recombinant HEK293T cell line is established, which can be used for high-throughput screening of GLP-1 receptor agonists.
10.Evolution and regional differences in the supportive environment for influenza vaccination among the elderly population in China.
Ping LI ; Zheng LIU ; Rui SHAN ; Zi Yan CHEN ; Jian Nan XU ; Wang Nan CAO ; Fu Qiang CUI
Chinese Journal of Preventive Medicine 2023;57(12):2064-2067
Seasonal influenza leads to a significant disease burden, and older people infected with influenza are susceptible to various complications. Influenza immunization can prevent infection effectively and significantly reduce the risk of complications and severe cases. Creating a supportive environment for vaccination is crucial in advancing the influenza vaccination rate among the elderly population. In China, the present environment for supporting influenza vaccinations among the elderly is primarily comprised of policies for free vaccination and expense reimbursement, which exhibit noteworthy regional variations across cities and regions. This study systematically analyses the supportive environment and regional disparities associated with influenza vaccination among the elderly in China. It aims to comprehend the opportunities for influenza prevention and control resulting from the current background of influenza vaccination and to identify potential health inequality challenges caused by regional differences. The findings should inform the introduction of relevant national policies and programs to protect the health and well-being of the elderly population.
Humans
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Aged
;
Health Status Disparities
;
Influenza, Human/prevention & control*
;
China
;
Cities
;
Vaccination

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